Security issues continue to be our focus for Jargon Watch terms. This week, we look at terms that concern protecting your network from hackers. The first article in our series focused on hacker terms, and last week’s Jargon Watch picked up more hacker words. Next week, we’ll look at firewalls.

Network address translation (NAT)Network address translation (NAT) is a standard that takes the individual IP address of each client on your network and translates it into a single IP address for the outside world—that is, the Internet—and vice versa. It also functions as a firewall because it keeps the individual client IP addresses hidden from potential hackers.

Proxy serversA proxy server is a firewall tool that provides a gateway for information coming and going on a network. It uses network address translation (NAT) to break a direct connection between sender and receiver. It then sends user requests out of ports different from the ones the responses come into. Proxy servers are available for Web access (an http proxy) and for e-mail (an SMTP proxy). The advantage of a proxy server is that it prevents hackers from getting internal IP addresses and other details from a client on a network.

Spoof / spoofingSince a spoof is a hoax or deception, spoofing can mean any kind of deception a hacker might use to gain access to someone else’s network. This includes faking an Internet address in order to deceive someone and gain illegal entry into a secure system.

Stateful inspectionA stateful inspection is a function of a firewall that tracks and makes sure the destination of an inbound packet matches the address of a previous outbound request. Blocking can be made at one of many steps in the process.

PorkjockeyThe phrase “when pigs fly” indicates a negative prediction—something is not likely to happen anytime soon. The shipping date of a beta version of software can fall into that category. In defiance of this prediction, porkjockeys are the programmers who fix bugs and other problems in the code, hoping to get the software (pork) launched.

Dog foodSoftware developers who “eat their own dog food” actually use and test the in-development software they are working on in order to identify any potential problems.

Egress filteringEgress filtering is the filtering of outbound traffic from your network. Egress filtering is done on border routers to make your network less appealing to potential hackers trolling for potential relay sites. It filters what is allowed out of your network in case something in your network is compromised or a hacker wants to use your network to launch further attacks using spoofed IP addresses. Egress filtering ensures that spoofed packets can’t leave your network.Next week, we'll feature additional terms about firewalls. If you'd like to suggest some security words, please send us an e-mail or post a comment below.